• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.384-388
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• 2010

Human microsomal prostaglandin E synthase-1 (mPGES-1) catalyzes the conversion of prostaglandin $H_2$ ($PGH_2$) into prostaglandin $E_2$ ($PGE_2$). To establish a stable and efficient method to assess the activity of mPGES-1, a coupled enzyme assay system using mPGES-1, 15-hydroxyprostaglandin dehydrogenase (15-PGDH) and phosphomolybdic acid (PMA) was developed. In this assay system, $PGH_2$ was converted to $PGE_2$ by mPGES-1, and then $PGE_2$ was further transformed to the 15-keto-$PGE_2$ by 15-PGDH accompanying the production of NADH, which was easily detected by fluorescence spectrometry in a multi-well plate format. During the reaction, spontaneous oxidation of $PGH_2$ was prevented by PMA. Using this novel assay, the $K_m$ value of mPGES-1 for $PGH_2$ and the $IC_{50}$ value of the previously characterized inhibitor, MK-886, were determined to be 0.150 mM and $2.8\;{\mu}M$, respectively, which were consistent with the previously reported values. In addition, low backgrounds were observed in the multi-wall plate screening of chemical compounds.

• 한국염색가공학회지
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• 제9권4호
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• pp.39-46
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• 1997

In this study, Two types of polyester fabrics were hydrolysed with NaOH using the CDR m/c of pad-steam type and the Sofleena m/c of liquor-flow type to determine the alkali hydrolysis properties of polyester fabrics. The results were as follows: Under the same conditions, the weight loss of charmeuse was about 0.5% and 2~3% higher than that of pebble with CDR m/c and with Sofleena m/c, respectively. The weft density of pebble decreased about 14picks/inch with CDR m/c and 3picks/inch with Sofleena m/c comparing to the untreated sample at 18% of weight loss, while the weft density of charmeuse decreased about 5picks/inch with CDR m/c and 2picks/inch with Sofleena m/c at 20% of weight toss. K/S value decreased almost identically within about 11% weight loss of pebble and 8% of charmeuse processed with both CDR and Sofleena. However, in the above these weight losses, K/S value of the fabrics processed with Sofleena was higher than that of fabrics processed with CDR. The bending rigidity of warp direction of the fabrics ($2{\times}10^{-2}gf.cm^2 /cm$ higher for charmeuse and ($7{\times}10^{-3}gf.cm^2 /cm$ higher for pebble) processed with CDR m/c was higher than that of the fabrics processed with Sofleena m/c.

• The Korean Journal of Physiology
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• 제2권2호
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• pp.53-61
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• 1968

Maximal oxygen debt, lactate and excess lactate were measured in 13 men with low hematocrit ratio before and after maximal exercise. Maximal exercise run was performed on a treadmill and the duration of run was 2 minutes 45 seconds in each subject. Hematocrit ratio ranged between 35 and 47%, the mean being 39.8%. The following results were obtained. 1. Maximal oxygen debt expressed on basis of body weight increased as the hematocrit ratio decreased. The correlation coefficient between the two was r= -0.770. 2. The time necessary for decreasing to 50% of total maximal $O_2$ debt(half time) became longer as the hematocrit ratio decreased. In normal men the half time was about 4 minutes and at the longest it was 12 minutes in men with the lowest hematocrit ratio. 3. The lactate concentration reached its peak value after 3 minutes of recovery. Thereafter, the time course of decrease in lactate concentration coincided roughly with that of respiratory oxygen debt curve. To reach to the resting level, however, it took longer time than that of respiratory oxygen debt. 4. Resting concentrations of lactate was 1.28 mM/l, pyruvate 0.13 mM/l and L/P ratio was 9.8. Peak value of ${\Delta}L$ after exercise reached to the value of 10.4 mM/l and ${\Delta}L/P$ reached 26.0. Peak excess lactate after exercise was 6.34 mM/l. 5. The part of oxygen debt accounted for by the oxygen equivalent of excess lactate was only 38.4%. A better relationship between lactate and oxygen debt was observed and the part of oxygen debt accounted for by the oxygen equivalent of lactate was 63.3%. 6. Peak value of lactate after maximal exercise increased as the hematocrit ratio decreased. 7. Respiratory oxygen debt of 100 ml/kg was accounted for by lactate more than 60% and only 30% was by excess lactate. 8. Excess lactate was not a good index of respiratory oxygen debt.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권2호
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• pp.960-973
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• 2018

This paper presents design for error correcting algorithm of the time of flight (ToF) detection value in the light detection and ranging (LIDAR) system sensor. The walk error of ToF value is generated by change of the received signal power depending on distance between the LIDAR sensor and object. The proposed method efficiently compensates the ToF value error by the independent ToF value calculation from the received signal using both rising point and falling point. A constant error of ~0.05 m is obtained after the walk error correction while an increasing error up to ~1 m is obtained with conventional method.

• Journal of Mechanical Science and Technology
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• 제16권11호
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• pp.1420-1427
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• 2002

The Monkman-Grant (M-G) and its modified parameters were evaluated for type 316LN and modified 9Cr-Mo stainless steels prepared with minor element variations. Several sets of creep data for the two alloy systems were obtained by constant-load creep tests in 550～650$\^{C}$ temperature range. The M-G parameters, m, m', C, and C' were proposed and discussed for the two alloy systems. The m value of the M-C relation was 0.90 in type 316LN steel and 0.84 in modified 9Cr-Mo steel. The m' value of the modified relation was 0.94 in type 316LN steel and 0.89 in 9Cr-Mo steel. Although creep fracture modes and creep properties between type 316LN and modified 9Cr-Mo steels showed a basic difference, the M-G and its modified relations demonstrated linearity quite well. The m' of modified relation almost overlapped regardless of the creep testing conditions and chemical variations in the two alloy systems, and the parameter m' was closer to unity than that of the M-G relation.

• 대한수의학회지
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• 제33권3호
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• pp.507-511
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• 1993

Captafol은 phthalimide계통의 항진균제로써 difolatan이란 상품명으로 개발되어 과일, 채소의 탄저병 및 원목 등의 곰팡이 구제에 널리 사용되고 있는 것으로 국내에서도 두번째로 많이 생산, 사용되는 품목이나 독성실험에 관한 보고는 거의 없는 상태이다. 이에 본 연구에서는 captafol 자체에 대한 독성기전의 일부를 확인하고자 동물체내에서 일어나는 여러가지 대사작용이 배제된 시험관내에서 실험을 수행하였다. 랫트 혈액을 후대정맥으로 부터 채혈하여 4개의 시험관에 $2.5m{\ell}$씩 분주한 후 captafol 농도가 $0.1{\times}10^{-4}M$, $1{\times}10^{-3}M$, $1{\times}10^{-2}M$이 되도록 한 ethanol용액 $25{\mu}{\ell}$씩 넣고 $CO_2$ incubator에서 2시간 동안 부드럽게 혼합하여 혈액학적 성상 및 적혈구 취약성 시험을 수행하였다. 또한 원심분리하여 얻어진 혈장에서 생화학적 성상 등을 조사한 결과 다음과 같은 성적을 얻었다. 1. 적혈구수 및 hematocrit치는 captafol 투여량에 비례적으로 유의한(p<0.05) 감소를 나타내었다. 2. 적혈구막 취약성 실험에서 $1{\times}10^{-3}M$ 및 $1{\times}10^{-2}M$ 농도에서 대조군에 비하여 유의한(p<0.01) 증가를 나타내었다. 3. 혈장내 potassium이온의 농도는 captafol의 투여량에 비례적으로 증가하였다. 4. Total bilirubin 및 creatine kinase가 대조군에 비하여 각각 증가 및 감소하였다.

• Journal of Biosystems Engineering
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• 제41권3호
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• pp.177-183
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• 2016

Purpose: Mee (Madhuca longifolia) is an economically important tree growing throughout Sri Lanka. Its importance is mainly attributed to its oil with high nutritional and medicinal values. However, an inefficient extraction method limits its use. This study revealed the possibility of extracting oil from mee seeds by using a screw-type oil expeller. Methods: A popular screw-type oil expeller was used in the experiment. Extract bar clearance and speeds of the main spiral shaft were altered to increase the oil expelling efficiency of the machine. The quality of refined oil at the optimum oil yield was determined by measuring the refractive index, saponification value, iodine value, unsaponifiable matter, free fatty acid, and specific gravity. Results: An optimum yield of 35% oil was obtained when the machine capacity was 30 kg/h and energy consumption was 0.13 kWh/kg. This optimum machine condition was observed at an extract bar clearance of 0.5 mm and a main spiral shaft speed of 90 rpm. The refractive index, saponification value, iodine value, unsaponifiable matter, free fatty acid, and specific gravity of the oil were 1.4, 203, 59, 3.5%, 0.2%, and 0.907 g/cm3 respectively. Color of the mee oil was closer to yellow, which is revealed by the lightness value (L) of 24.93 and positive value (b) of 11.81. Conclusion: The screw-type oil expeller can be used for economically extracting mee oil on a commercial scale.

• 태양에너지
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• 제20권2호
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• pp.31-42
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• 2000

Since the direct normal insolation is a main factor for designing any focusing solar system, it is necessary to evaluate its characteristics all over the country. We have begun collecting direct normal insolation data since December 1990 at 16 different locations and considerable effort has been made for constructing a standard value from measured data at each station. KIER(Korea Institute of Energy Research)'s new data will be extensively used by concentrating system users or designers as well as by research institutes. From the results, we can conclude that 1) Yearly mean $4,576kcal/m^2.day$ of the direct normal insolation was evaluated for clear day all over 16 areas in Korea. 2) Clear day's direct normal insolation of spring and summer were $4,710kcal/m^2.day$ and $4,960kcal/m^2.day$, and for fall and winter their values were $4,484kcal/m^2.day$ and $4,151kcal/m^2.day$ respectively. So, spring and summer were higher, and fall and winter were lower than the yearly mean value.

• Biomolecules & Therapeutics
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• 제31권1호
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• pp.82-88
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• 2023

Genomic analysis indicated that the genome of Drosophila melanogaster contains more than 80 cytochrome P450 genes. To date, the enzymatic activity of these P450s has not been extensively studied. Here, the biochemical properties of CYP6A8 were characterized. CYP6A8 was cloned into the pCW vector, and its recombinant enzyme was expressed in Escherichia coli and purified using Ni²⁺-nitrilotriacetate affinity chromatography. Its expression level was approximately 130 nmol per liter of culture. Purified CYP6A8 exhibited a low-spin state in the absolute spectra of the ferric forms. Binding titration analysis indicated that lauric acid and capric acid produced type I spectral changes, with K_d values 28 ± 4 and 144 ± 20 µM, respectively. Ultra-performance liquid chromatography-mass spectrometry analysis showed that the oxidation reaction of lauric acid produced (ω-1)-hydroxylated lauric acid as a major product and ω-hydroxy-lauric acid as a minor product. Steady-state kinetic analysis of lauric acid hydroxylation yielded a k_cat value of 0.038 ± 0.002 min^-1 and a K_m value of 10 ± 2 µM. In addition, capric acid hydroxylation of CYP6A8 yielded kinetic parameters with a k_cat value of 0.135 ± 0.007 min^-1 and a K_m value of 21 ± 4 µM. Because of the importance of various lipids as carbon sources, the metabolic analysis of fatty acids using CYP6A8 in this study can provide an understanding of the biochemical roles of P450 enzymes in many insects, including Drosophila melanogaster.

• 한국식품조리과학회지
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• 제30권4호
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• pp.394-401
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• 2014

본 연구는 연잎추출물이 우육포의 품질특성에 미치는 영향을 검토하였다. 우육포는 물 100 mL 첨가(T0), 물 60 mL와 연잎추출물 40 mL 첨가(T1), 물 40 mL와 연잎추출물 60 mL 첨가(T2) 그리고 연잎추출물 100 mL 첨가(T3)한 것 등 네 종류를 제조하였다. 우육포의 수분, 단백질, 지방 및 회분은 시료들 사이에 유의한 차이가 없었다. 총 유리아미노산함량은 T0가 가장 높고, T3가 가장 낮았다(p<0.05). 표면색깔 중 L- 및 b-value는 시료들 사이에 유의한 차이가 없었지만 a-value는 T3가 가장 높았다(p<0.05). 경도, 탄성, 응집성, 뭉침성 및 씹힘성은 시료들 사이에 유의한 차이가 없었다. 수분활성도 및 pH는 시료들 사이에 유의한 차이가 없었다. TBARS값 및 총균수는 T0 및 T1보다 T2 및 T3가 유의하게 낮았다(p<0.05). VBN함량은 T3가 가장 낮았다(p<0.05). 풍미, 맛, 조직감, 다즙성 및 전체적인 기호성은 시료들 사이에 유의한 차이가 없었지만 색깔은 T3가 가장 우수하였다(p<0.05).